Engine oil level rising Westerbeke 58

[NYSail]

Change your oil & filter. Put the specified amount of oil in the engine as per the service manual.
Make sure your boat is not listing to port or starboard, fore or aft. (have you added a lot of weight to the boat recently?)
Run the engine for few minutes, until warm. Pull the dipstick, wipe it clean, insert and take note of where it is on the stick.
Mark the dipstick. That is your new normal. See what happens.

i would not just add the specified amount in unless you know you got all of the old oil out. Using an oil extractor on some engines may leave a fair amount of old oil. What I have done is marked on my extractor every half quart up to the top. Did this by adding exactly a half quart of water in at a time so I know almost exactly how much I pull out. Also pour my filter into the extractor. I would rather start with a little less than over fill right from the start.

good luck
Greg